Swansea City director John van Zweden has taken a jibe at Holland forward Dirk Kuyt for a collision that rules Jonathan de Guzman out of the club's opening day clash against Manchester United.

De Guzman was diagnosed with a concussion after a training-day clash of heads with Kuyt, ahead of Holland's friendly against Portugal.

It meant De Guzman not only missed the international fixture, but also ensured that Swansea will be without his services when the Premier League champions visit Wales on Saturday.

The player himself has revealed he needs several days of rest before returning to match fitness, and Swans director Van Zweden yesterday tweeted: "Thanks Dirk Kuyt for your rough action! Now De Guzman is out for our game."

De Guzman is currently at the Liberty Stadium on loan from Villarreal, and made 37 league appearances last season for Swansea.

Following the training session incident, he released a statement yesterday via his personal website that read: "I was taken to hospital for tests and the initial diagnosis is a mild concussion.

"Unfortunately I will miss the [friendly] as I need seven to 10 days rest. It also means that I will miss the season opener for Swansea City against Manchester United. I still hope to play as soon as possible."